SARS-CoV nucleoprotein from S. cerevisiae, frozen
Description: Severe acute respiratory syndrome coronavirus (SARS-CoV) recombinant Nucleoprotein (SCoV-rN) expressed in yeast Saccharomyces cerevisiae. UniProtKB sequence accession number: P59595 (NCAP_SARS), expressed with N-terminal His6-tag. It was purified from yeast lysates under native (non-denaturing) conditions using convenient chromatographic techniques. The final product is formulated in PBS (pH 7.4).
Form: Frozen liquid in PBS (pH 7.4).
Safety: Product 20-S1N-ScB-F contains only yeast expressed proteins that are not infectious or hazard. Contains no plasma or serum of animal origin. No safety precautions are required.
Storage: The product is shipped with dry ice (shipment cost to Europe: 160 €). Store at -80°C for the long term. After thawing may be stored for short-term at 4°C (stable at least 1 week at this temperature). Avoid repeated freeze/thaw cycles.
Concentration: 0.3 mg/ml (Lot dependent).
Image: SDS-PAGE showing SCoV-rN product 20-S1N-ScB-F at approximately 48 kDa (1 μg/lane).
Purity: ~90% pure intact form of SCoV2-rN protein as determined by SDS-PAGE.
Applications: ELISA, other immunoassays, Western blot, SDS-PAGE.
Reactivity of SCoV-rN protein (product 20-S1N-ScB-F) with anti-SARS-CoV-2 IgG in ELISA using Covid-19 positive and negative human sera: this product has been used as a control for SARS-CoV-2 recombinant proteins in ELISA and S1 antigen-based CE-approved commercial IVD tests using the same set of human sera. It has shown very similar results to SARS-CoV-2 recombinant nucleoprotein product due to high degree of similarity (sequence identity of SARS-CoV and SARS-CoV-2 nucleoproteins is >90%). Therefore, SCoV-rN nucleoprotein may also be used for the detection of specific antibodies against SARS-CoV-2. Still, SCoV2-rN showed higher reactivity with specific antibodies in Covid-19 positive sera. Results for sensitivity and specificity are provided in the Table below:
|Reference test for Covid-19 positive sera||RT-PCR|
Analyzed antigens or
(# 20-S1N-ScB-F) IgG
(from E.coli) IgG
(# 20-S2N-ScA-F) IgG
|SARS2 S1 IgG
|AMP rapid (S1) IgG test||Euroimmun ELISA (S1) IgG test|
|Sensitivity (n=50), correct positives||92.00%||92.00%||92.00%||78.00%||90.00%||90.00%|
|Specificity (n=150), correct negatives||99.33%||94.00%||99.33%||97.33%||99.33%||98.67%|
|OD mean for positive sera (n=50)||1,967||1,455||2,502||0,980||N. A.||1,820|
|100 μg||20-S1N-ScB-F-C||500 €||Inquiry / Order